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ATMEGA644PA-PU

MCHPATMEGA644PA-PU

Microchip Technology
AVR AVR® ATmega Microcontroller IC 8-Bit 20MHz 64KB (32K x 16) FLASH 40-PDIP
Active1,041 in stock
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Overview

The ATMEGA644PA-PU is a high-performance, low-power 8-bit AVR microcontroller featuring 64KB of flash memory and 4KB of SRAM in a user-friendly 40-pin PDIP package. It utilizes the AVR enhanced RISC architecture to execute most instructions in a single clock cycle, achieving throughputs up to 20 MIPS at 20MHz. This specific variant features picoPower technology for ultra-low power consumption in sleep modes, making it ideal for battery-operated applications.

Why Choose This Part

This MCU offers a generous 64KB flash and 4KB RAM capacity in a through-hole format, which is rare for modern high-density microcontrollers. The inclusion of a dedicated 2KB EEPROM ensures robust non-volatile data storage for configuration and calibration constants without consuming program flash.

Applications

Industrial Control Systems
Utilizing 32 programmable I/O lines and an integrated 2-cycle multiplier for real-time processing of industrial sensor data.
Battery-Powered Instrumentation
Leveraging picoPower modes with sleep currents as low as 0.6 uA to extend the life of portable measurement devices.
Prototyping and Education
The 40-pin through-hole DIP package allows for easy use on breadboards and socketed development without surface-mount soldering.
Legacy System Replacement
Providing a modern, low-power upgrade path for older 8-bit designs requiring significant I/O and program space.

Key Specifications

Speed 20MHz
RAM Size 4K x 8
Core Size 8-Bit
EEPROM Size 2K x 8
Peripherals Brown-out Detect/Reset, POR, PWM, WDT
Connectivity I2C, SPI, UART/USART
Mounting Type Through Hole
Number of I/O 32
Core Processor AVR
Package / Case 40-DIP (0.600", 15.24mm)
Data Converters A/D 8x10b
Oscillator Type Internal
Program Memory Size 64KB (32K x 16)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 40-PDIP
Voltage - Supply (Vcc/Vdd) 1.8V ~ 5.5V

Getting Started

Developers can program the ATMEGA644PA-PU using the Microchip Studio IDE (formerly Atmel Studio) and hardware tools like the MPLAB PICkit 5 or AVRISP mkII. For breadboard development, ensure a regulated 1.8V to 5.5V supply and an external crystal if 20MHz operation is required, as the internal oscillator is calibrated for lower speeds.

Part of AVR ATmega family » ATMEGA644PA

ATMEGA644PA Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Package Stock
ATMEGA644PA-PU (this part) DIP-40 1,041
ATMEGA644PA-AU TQFP-44 1,042
ATMEGA644PA-MU VFQFN-44 619

Also Consider

ATMEGA328P-PU MCHPMicrochip Technology - A more common 28-pin alternative for smaller projects with lower I/O requirements and 32KB of flash.

Categories

Microcontrollers > AVR
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